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Enhanced colour encoding of materials discrimination information for multiple view dual-energy x-ray imaging
No full textThis thesis reports an investigation into dual-energy X-ray discrimination techniques. These techniques are designed to provide colour-coded materials discrimination information in a sequence of perspective images exhibiting sequential parallax. The methods developed are combined with a novel 3D imaging technique employing depth from motion or kinetic depth effect (KDE). This technique when applied to X-ray images is termed KDEX imaging and was developed previously by the university team for luggage screening applications at security checkpoints. A primary motivation for this research is that the dual-energy X-ray techniques, which are routinely incorporated into ‘standard’ 2D luggage scanners, provide relatively crude materials discrimination information. In this work it was critical that robust materials discrimination and colour encoding process was implemented as the sequential parallax exhibited by the KDEX imagery may introduce colour changes, due to the different X-ray beam paths associated with each perspective image. Any introduction of ‘colour noise’ into the resultant image sequences could affect the perception of depth and hinder the ongoing assessment of the potential utility of the dual-energy KDEX technique. Two dual-energy discrimination methods have been developed, termed K-II and W-E respectively. Employing the total amount of attenuation measured at each energy level and the weight fraction of layered structures, a combination of the K-II and the W-E techniques enables the computation and extraction of a target objects’ effective atomic number (Zeff) and its surface density (ρS) in the presence of masking layers
Decision Support System for Desertification mitigation in the Agri basin, southern Italy, Physics and Chemistry of the Earth 28
No full textDecision support system for desertification mitigation in the Agri basin, southern Italy
No full textAs a contribution to understanding the interaction between the factors which influence desertification, a decision support system (DSS) is developed for the 1700-km2 Agri basin in southern Italy. This integrates the SHETRAN physically based hydrological and sediment yield model, a simple socio-economic model (in which farmers select those crops which give the highest income relative to cost of production), a database (containing climate, physical and socio-economic data according to a range of future scenarios) and existing desertification management experience into a single tool to aid decision-making in desertification mitigation. It provides a means of examining the effect of climate change and land management on desertification, allowing for feedback between the physical conditions and land use as determined by farmer decisions and government or EU agricultural policy (especially crop subsidies). Typical issues which the DSS can address include: what are the desertification consequences of specified climate scenarios, within a context of fixed agricultural policy?; and, given a climate scenario, is a specified land use or agricultural policy sustainable?</p
Tag Group Authentication Using Bit-Collisions
No full textSecure RFID systems should be able to authenticate individual tags to prevent genuine items from being replaced with forgeries. Conventional authentication protocols would require some form of challenge-response exchange with each individual tag. The extra transaction time needed to authenticate each individual tag sequentially might not be practically feasible, especially when readers are required to process an ever increasing volume of tagged items within a limited time. Our proposal works towards an approach that allows for multiple tags in a group to be authenticated simultaneously, as all the tags transmit their responses to a single challenge at the same time. This results in a controlled bit-collision pattern that can be used to verify that all the individual tags in a group are present and genuine.Computer Science, Theory & MethodsEngineering, Electrical & ElectronicEICPCI-S(ISTP)
Guo leng ba gui he jin de wei guan jie gou
No full textDing, Heyi = 過冷鈀硅合金的微觀結構 / 丁赫一.Thesis M.Phil. Chinese University of Hong Kong 2014.Includes bibliographical references.Abstracts also in Chinese.Title from PDF title page (viewed on 15, November, 2016).Ding, Heyi = Guo leng ba gui he jin de wei guan jie gou / Ding Heyi
Scattered countable metric spaces X for which X × X ≈ X
No full textAs an application of [2], we shall give a characterization of locally compact countable metric spaces X for which X × X ≈ X, namely X ≈ LC(ωγ) if leng (X) > 1. We shall also give 2ℵ0 many scattered countable metric spaces X for which X × X ≈ X.In a classical paper ([1]), Mazurkiewicz and Sierpiński counted the number of locally compact countable metric spaces and scattered countable metric spaces. The former was found to be ℵ1 and the latter to be 2ℵ0. We shall show that there are sufficiently many scattered countable metric spaces X for which X × X ≈ X.departmental bulletin pape
Supplementary_table_1 - Treatment Strategy for Unruptured Intracranial Aneurysm in Elderly Patients: Coiling, Clipping, or Conservative?
No full textSupplementary_table_1 for Treatment Strategy for Unruptured Intracranial Aneurysm in Elderly Patients: Coiling, Clipping, or Conservative? by H. Yang, H. Jiang, W. Ni, B. Leng, X. Bin, G. Chen, Y. Tian, and Y. Gu in Cell Transplantation</p
Chao leng xuan liang hun he wu zhong de yi he jian xiang gan zi xuan dong li xue
No full textLi, Xiaoke = 超冷旋量混合物中的異核間相干自旋動力學 / 李小科.Thesis Ph.D. Chinese University of Hong Kong 2015.Includes bibliographical references (leaves 126-142).Abstracts also in Chinese.Title from PDF title page (viewed on 25, October, 2016).Li, Xiaoke = Chao leng xuan liang hun he wu zhong de yi he jian xiang gan zi xuan dong li xue / Li Xiaoke
Yong yu you hua zhi bei chao leng yuan zi hun he wu de guang xue ou ji jing
No full textChen, Jun = 用於優化製備超冷原子混合物的光學偶極阱 / 陳軍.Thesis M.Phil. Chinese University of Hong Kong 2014.Includes bibliographical references (leaves 109-117).Abstracts also in Chinese.Title from PDF title page (viewed on 29, November, 2016).Chen, Jun = Yong yu you hua zhi bei chao leng yuan zi hun he wu de guang xue ou ji jing / Chen Jun
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